What happens if you only eat fruit for two weeks?

November 24, 2025 •

3 min read

According to nutritionists, adhering to a fruit-only diet for any significant length of time can lead to dangerous nutritional deficiencies. While fruit is a healthy part of a balanced diet, this article explores what happens if you only eat fruit for two weeks and the serious health complications that can arise.

Quick Summary

A two-week fruit-only diet can lead to rapid, but temporary, weight loss, and an initial energy boost. However, it quickly results in severe nutrient deficiencies, muscle loss, and blood sugar instability. The diet is highly restrictive, unsustainable, and poses serious health risks, including a slowed metabolism and potential long-term organ strain.

Key Points

Nutrient Deficiencies: A two-week fruit-only diet leads to deficiencies in vital nutrients like protein, vitamin B12, calcium, and iron.
Initial Weight Loss is Water Weight: The initial rapid weight loss is primarily from water and muscle mass, not fat, and is quickly regained.
Blood Sugar Imbalance: High fructose intake can cause significant blood sugar spikes and crashes, which is especially dangerous for diabetics.
Muscle Loss and Fatigue: The lack of protein results in muscle wasting, a slowed metabolism, and persistent fatigue.
Mental and Digestive Issues: The restrictive nature can trigger food obsession and disordered eating, alongside digestive discomfort like bloating and gas.
Dental Health Risks: The high sugar and acid content in fruit can erode tooth enamel and increase the risk of cavities.
Not Recommended by Experts: Health professionals advise against this extreme diet, favoring a balanced approach for sustainable, long-term health benefits.

A diet consisting solely of fruit for two weeks, often termed a fruitarian diet, is highly restrictive and not recommended by health professionals. While there might be an initial feeling of lightness and increased energy due to reduced calorie intake and fruit's high water content, this is short-lived and does not indicate true health benefits. The high fiber content can initially aid bowel movements but may also cause gas and bloating.

The Health Risks of a Two-Week Fruit-Only Diet

By day three or four, the body begins to suffer from the lack of essential nutrients found outside of fruit, leading to fatigue and a significant drop in energy. A fruit-only diet is severely deficient in several key areas necessary for proper bodily function:

Critical Nutritional Deficiencies

A two-week fruit diet lacks vital nutrients including protein, necessary for muscle health and metabolism; healthy fats, crucial for brain function and hormone production; Vitamin B12, essential for preventing anemia and neurological issues; calcium and Vitamin D for bone health; and iron and zinc, important for immune function. The absence of these can lead to muscle wasting, fatigue, and other health complications.

Blood Sugar and Dental Health Concerns

The natural sugars in fruit, particularly fructose, can cause significant fluctuations in blood sugar levels, which is especially risky for individuals with diabetes or insulin resistance. Additionally, the acidity and sugar content of many fruits can contribute to dental enamel erosion and cavities over time.

Comparing Fruit-Only to a Balanced Diet


Feature	Two-Week Fruit-Only Diet	Healthy, Balanced Diet
Weight Loss	Rapid, primarily water and muscle mass, unsustainable.	Gradual, healthy fat loss, sustainable long-term.
Nutrient Profile	High in fiber, vitamins A and C, but severely deficient in protein, B12, calcium, and fat.	Rich in all essential macronutrients, vitamins, and minerals.
Energy Levels	Initial spike followed by significant crashes and fatigue.	Stable, sustained energy throughout the day.
Satiety	Temporary fullness due to water and fiber, but lack of protein and fat leads to constant cravings.	Long-lasting fullness from a combination of fiber, protein, and healthy fats.
Digestive Health	Potential for initial distress, high fiber can cause gas and bloating.	Promotes healthy gut microbiome with diverse food sources.
Long-Term Risk	Malnutrition, muscle loss, organ strain, and potential eating disorders.	Supports long-term health and reduces risk of many chronic diseases.

The Potential Aftermath

Transitioning off a two-week fruit-only diet can lead to regaining lost water and muscle weight quickly. The digestive system may struggle to readjust to a normal diet. Such restrictive diets can also foster unhealthy psychological relationships with food, potentially leading to disordered eating patterns. The idea of a 'detox' through a fruit-only diet is not supported by science, as the body's organs already perform detoxification effectively.

Conclusion: Avoid a Fruit-Only Diet

While fruit is beneficial as part of a healthy eating plan, a two-week fruit-only diet is neither sustainable nor safe. It inevitably leads to significant nutritional deficiencies and health risks. A balanced diet including various food groups is the recommended path for long-term health. Always consult a healthcare professional before starting any restrictive diet.

For reliable information on healthy eating, refer to resources such as the NHS guide on a balanced diet: https://www.nhs.uk/live-well/eat-well/5-a-day/why-5-a-day/.

Frequently Asked Questions

No, it is not safe to do a fruit-only diet for two weeks. It can lead to severe nutritional deficiencies, muscle loss, and blood sugar instability, and is not recommended by health experts.

You may experience initial weight loss, but it will mostly be water weight and muscle mass, not fat. The weight is likely to be regained once you stop the diet.

On a fruit-only diet, you will be missing essential nutrients including protein, healthy fats, vitamin B12, calcium, vitamin D, iron, and zinc.

No, the concept of a 'fruit detox' is a myth. The body is equipped with its own detoxification systems via organs like the liver and kidneys, and a restrictive diet does not improve this process.

While the sugar in whole fruit comes with fiber, excessive intake, especially without balancing it with other nutrients, can cause blood sugar spikes and potentially lead to health issues, particularly for those with diabetes.

The long-term effects of an extended fruitarian diet can be severe malnutrition, osteoporosis, kidney and liver problems, muscle loss, and, in extreme cases, multi-organ dysfunction.

A much healthier alternative is a balanced and varied diet that incorporates plenty of fruits alongside vegetables, lean proteins, healthy fats, and whole grains.